Process for covering with a protective plastic coating flattened strips and product thereof.



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E. GUICHARD. v v H A PROTECTIVEP LASTIC COATING FLAT TENED STRIPS AND PHQDUCT wuuaor. APPLICATION FILED SEPT. 9, I914.

Patented J une 19, 1917.

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EDGAR GUICHARD, OF ETAMPES, FRANCE.

PROCESS FOR COVERING WITH..A PROTECTIVE PLASTIC COATING FLATTENED STRIPS AND PRODUCT THEREOF. I

Specification of Letters Patent.

Patented June 19, 191.7.

Application filed September 9, 1914. Serial No. 860,854.

To all whom it may concern:

Be it known that I, EDGAR GUICHA-RD, a citizen of the French Republic, and residing in Etampes, Seine-et-Oise, France, Mouhn de' la Pirouette, engineer, have invented certain new and useful Improvements in and Relating to Process for Covering with a Protective Plastic Coating Flattened Strips and Product Thereof, of which the following is a complete specification.

My invention relates to a process for covering flattened strips with -plastic materlal so that the strip in cross section has a-covering increasing gradually from the center toward the edges. Hitherto flattened strips have been covered with plastic material so as to have in cross section of the strip a uniform thickness. of coating. When a strip uniformly coated is dried the coating thereof contracts, reducing the thickness at the edges, With my processbf covering, when the coating on the strips is dry, thecontraction of the coating will spread the covering uniformly and the thickness thereof willbe the same over the whole cross section of the strip, or, better still, a greater thickness of coating will remain at the edges of the strip vsoas to more effectively protect the said edges.

The accompanying drawings illustrate by way of example a form of machine for carrying the process into effect, this machine being more particularly suitable for covering corset steels with celluloid.

Figure 1 is a vertical section of the ma- Fig. 2 is an end view on the draw from the interior.

The machine shown comprises a hopper a, of any suitable form, for the solution of celluloid, which is preferably in apasty state, that is to say, it will contain only a comparatively small proportion of solvent. The hopper is supported by an operating chamber 6, with which it communicates. On one side of the chamber is a guide cxfor introducing the steels to be covered. Alining,

with the guide 0 is another guide d positioned within the chamber 6 and leading to a draw plate Z. The draw plate has an opening j the size of which can be varied by the elements 6 and 7 provided at the inner side of the draw-plate and adapted to be .regulated by means of the screws 9 and h respectively. The ends of these elements plate are rounded, as shown in Fig. 2, and with the rounded ends 71 of the groove j the same cooperate, so that the space between the steel and the sides of the openings in the drawplate has a greater width at the edges of the steel than at the center of its faces. At the exit from the draw plate there is-arranged a drying bench is to receive the coated steels issuing from the draw plate.-

The covering of the steels is accomplished as follows: The steels, cut to the required length, are introduced bythe guide 0 into the steeping chamber 6 wherefrom they are directed by the internal guide d in which the steel moves with a certain amount of play to the draw-plate Z. In the interior of the steeping chamber, and-mainly in the hollow space between the rear cndof the guide (Z and the draw-plate, the celluloid in solution submerges the steel, and when issuing from the draw-plate it bears a coating of pasty celluloid, the section of the coated steel beingexactly of the form of the opening in the draw-plate formed by the roundedthat the steel is coated with great regularity over its entire surface but to a greater extent on its edges, which, as is well known, wear out sooner than the face.

It is self-evident that the machine may be utilized for covering continuous "strips, which may be carried, by way of example, on a revolving'bobbin placed'in front of the guide a and rolled on to a drum placed on the right side of the bench k.

From the above description it will be seen I that by means of my process steels may be coated or covered with a plastic material so that the coating formed is ofa greater thickness at the edges than in the middle of the strip, and, consequently, when such a coated strip is'dried the contraction of the plastic material will tend to reduce the thickness at its edges, thus bringing the coating to a sub-' stantially uniform thickness over the entire strip. and,"inore probable still, leaving a greater thickness at the edges .of the strip, which, as previously described, is still more beneficial than the formation of a uniform the covering at the edges is greater than in themiddle. V

2. A process for covering flattened strips consisting in coating the strips with plastic material by a single operation so thatthe thickness of the covering decreases uniformly from thellongitudinal edges toward the middle of the strlp.

3. A process for covering flattened stripswhich'con'sists in covering the strips'with plastic material, scraping oil the excessof material from the strip in such a way that a larger quantity of the covering substance will remain on the edges of the strip' than on the face thereof and the covering formed I 4. A process coating flattened strips which consists in covering the strips with plastic material, then scraping OK the excess of plastic material to term a coating on the strip, thethickness'of 'vs hi ch increases gradually from themiddle to the edges of the then drying the strip, the coating at the edges being of such a thickness that under contraction its thickness will not become, less than the thickness of the coating in the middle of the strip.

5. A flattened strip having a seamless, in

casing coating, the cross'section of w ich coating adually increases from the mi dle to the e ges thereof. 7 In testimonywhereof Ivhave hereunto set my hand at Paris (France), this twenty-first day of August,-19l4. v

' EDGAR 'GUICHABD. In the presence of two witnesses:

Gmmnns PIER E RnBoU'rnL, JEAN LALAURET. 

